Environment Agency report on MTBE in groundwater

The Environment Agency, in partnership with the Institute of Petroleum, has produced a new report on the extent of groundwater contamination with the petrol component methyl-tertiary-butyl- ether (MTBE). The report, A review of current MTBE usage and occurence in groundwater of England and Wales, is the result of an intensive review of known MTBE pollution data and brings together information from the Agency, water companies, oil companies and fuel retailers.

In the US the Clean Air Act was introduced to help to improve emissions from motor vehicles. Oxygenate ether compounds such as MTBE were incorporated into motor fuels to meet the requirements of the Act in order to improve combustion and hence air quality.

Recently, however, MTBE has come to be seen as one of the most significant pollution threats facing the US. Although it may benefit air quality, poor management of stored fuel and leaks from underground tanks have brought major groundwater pollution problems. As such, US regulatory authorities are now seeking to remove the mandate for MTBE in fuels.

The situation in Europe and the UK is less clear. The new report, which follows the 1996 report Threat to potable groundwater supplies from the fuel additive MTBE, highlights:

much lower concentrations of MTBE in UK fuels (approximately one tenth of that used in US fuel);

greater distances between potential spill sites and water supply boreholes in the UK;

very different geology and water supply infrastructure likely to be more protective of public water supplies here; and

greater incentive for good fuel storage due to higher costs in the UK.

A full copy of the report is available from HMSO, priced £30. Tel: 0870 600 5522.